Development of polymorphic simple sequence repeat markers in Juglans regia L.

Walnut (Juglans regia L.) is one of the most important species in the Juglans genus. Simple sequence repeats (SSRs) are considered as the marker of choice owing to their codominant nature. This study aimed to develop a set of polymorphic SSRs from Class I repeats by using DNA sequences of the 'Chandler' cultivar. In all,800 SSRs were designed and tested in 8 Turkish, 3 French and 5 USA walnut cultivars, 88 (11%) did not produce bands, 161 (20.1%) were monomorphic and 551 (68.9%) were polymorphic. A set of 20 SSRs was selected for their high genetic diversity values using them in further genetic studies in walnut. The novel SSR markers developed in this study could be used in future studies for constructing a genetic linkage map, analyzing population genetics, identifying parents, and conducting marker-assisted breeding, finger printing and germplasm characterization in walnut.